DM and R2RML should use same datatype mapping

This is a Last Call comment on the Direct Mapping and R2RML specifications:

http://www.w3.org/TR/2011/WD-rdb-direct-mapping-20110324/
http://www.w3.org/TR/2011/WD-r2rml-20110920/


Both specifications define a mapping from SQL datatyped values to RDF literals.

http://www.w3.org/TR/2011/WD-rdb-direct-mapping-20110920/#defn-literal_map
http://www.w3.org/TR/2011/WD-r2rml-20110920/#datatype-conversions

The two mappings differ in various details. Given that the requirements for both mappings are the same, this places undue burden on implementers that plan to implement both the Direct Mapping and R2RML.

Therefore, both specifications should use the same mapping.

I note that the mapping in R2RML is based on the SQL-to-XML mapping in ISO/IEC 9075-14:2008, and covers more of SQL 2008 than the mapping in the DM.

I therefore propose that the mapping from the R2RML specification is used in both documents, with the DM specification using a normative reference to the R2RML spec.

Best,
Richard

Received on Thursday, 27 October 2011 10:27:39 UTC